ION EXCHANGE

It is widely used in the food & beverage, hydrometallurgical, metals finishing, chemical & petrochemical, pharmaceutical, sugar & sweeteners, ground & potable water, nuclear, softening & industrial water, semiconductor, power, and a host of other industries.

Most typical example of application is preparation of high purity water for power engineering, electronic and nuclear industries; i.e. polymeric or mineralic insoluble ion exchangers are widely used for water softening, water purification, water decontamination, etc.

Pre-treatment for Reverse Osmosis

It can be used to remove hardness from water by exchanging calcium and magnesium ions for hydrogen and chlorine ions in an ion exchange column. Hardness is one of the main causes for membrane fouling  so it’s common to use softeners (ion exchange resins) to extend membranes life.

Residential

It is used in the household (laundry detergents and water filters) to produce soft water, this is accomplished by exchanging calcium Ca2+ and magnesium Mg2+ cations against Na+ or H+ cations (see water softening).

Industrial

Industrial and analytical ion exchange chromatography is another area to be mentioned. This chromatography is a chromatographical method that is widely used for chemical analysis and separation of ions. For example, in biochemistry it is widely used to separate charged molecules such as proteins. An important area of the application is extraction and purification of biologically produced substances such as proteins and amino acids (e.g. DNA and RNA).

Ion-exchange processes are used to separate and purify metals, including separating uranium from plutonium and other actinides, including thorium, and lanthanum,neodymium, ytterbium, samarium, lutetium, from each other and the other lanthanides. There are two series of rare earth metals, the lanthanides and the actinides, both of which families all have very similar chemical and physical properties. Ion-exchange used to be the only practical way to separate them in large quantities, until the advent of solvent extraction techniques which can be scaled up enormously.

Nuclear

A very important case is the PUREX process (plutonium-uranium extraction process). This is used to separate the plutonium and the uranium from the spent fuel products from a nuclear reactor, and to be able to dispose of the waste products. Then, the plutonium and uranium are available for making nuclear-energy materials, such as new reactor fuel and nuclear weapons.

The ion-exchange process is also used to separate other sets of very similar chemical elements, such as zirconium and hafnium, which incidentally is also very important for the nuclear industry. Zirconium is practically transparent to free neutrons, used in building reactors. In contrast, hafnium is a very strong absorber of neutrons, used in reactor control rods.

For nuclear reprocessing and the treatment of radioactive waste, Ion exchangers are used.

Ion exchange resins in the form of thin membranes are used in chloralkali process, fuel cells and vanadium redox batteries.